We have developed techniques for the isolation of human globin chain-specific HnRNA and genomic DNA sequences, making use of affinity chromatography columns. The position of specific globin genes in restriction fragments of genomic fragments of genomic DNA is also under study. We have isolated recombinant plasmids containing double strand cDNA sequences prepared from alpha-globin, beta-globin and gamma-globin mRNAs. Each of these is now fully characterized. The staff members concerned with this application will continue these studies for normal human globin genes. They will investigate the sequence conplexity of the gene sequences adjacent to the gamma- and beta-globin structual genes, by analysis of both the genomic DNA directly and by study of HnRNA. Because of the evidence that there are sequences inserted into the coding compare DNA, HnRNA and mRNA for the different globin genes. In this way possible roles for these inserted non-coding sequences in transcriptional and processing regulation can be studied. If it proves possible to isolate genomic DNA fragments which can be reassociated with nuclear proteins to form a transcriptionally active complex ('chromatin'), attempts will be made to isolate the effector molecules active in mediating the gamma-globin to beta-globin switch.